Carburetor choke-valve control



Mar. '3, 1925. 1,528,484 E. HOLLEY CARBURETOR CHOKE VALVE CONTROL FiledJan. 12, 1922 NVENTOR.

Patented Mar. 3, 1925 1,528,484 PATENT OFFICE.

mm. HOLLEY, or nnraorr, MICHIGAN.

omunn'ron cnoxn-vanvn com-non.

Application filed January 12, 1922. Serial No. 528,882. I

To all whom it may concern:

Be it known that I, EARL HOLLEY, a citizen of the United States,residing at 2253 Burns Avenue, Detroit, in the county of Wayne and Stateof Michigan, have in-' vented certain new and useful Improvements inCarburetor Choke-Valve Controls, of which the following is aspecification.

This invention relates to a new and useful carburetor choke valvecontrol of which the following is a description of the preferredconstruction, reference being had to thi? drawings as follows operation,the electrical connections being shown diagrammatically.

Figure II shows diagrammatically the type of choke valve referred to.

Figure III shows in detail the manual control of the choke valve.

Like letters correspond to similar parts in all the figures.

The purpose of the invention is to eliminate the following difficultyexperienced with existing choke valve control.

If the choke valve spring be sufliciently stiff so that within theavailable are of movement (110) the choke valve may be moved from fullopen position to the closed position necessa for starting in coldweather withan' electric starter, the available range for driving awayis 0111 a relatively small angular movement an the adjustment iscorrespondingly coarse.

With the proposed means, the full swing of the control lever for thechoke valve is available.

Another difiiculty experienced with existin choke valve control is thefact that the right adjustment. of the tension in the automatic chokevalve for driving away will not give a sufficiently rich mixture forstartin the driver having to change the choke va ve adjustment themoment the engine fires.

If the choke is interconnected with the switch of the starting motorssothat the choke valve is closed regardless of manual adjustment of thechoke valve, an excessive-. 1y rich mixture will be given the motor atall times. -When restarting a hot motor, after stalling in traflic,theengine would thereupon be choked with excess fuel and a completeengine failure would result. This serious difficulty is avoided by theinvention described herein.

gure I shows the general scheme of Descfiptz'onrFigure I shows all theessential elements of this invention. A is the choke valve; Bis theshaft upon which the choke valve is eccentrically mounted; C is asquared portion at the end of B; D is a disk engaging with the squaredportion C; E is a light spring which slides the disk D along the end ofC which is threaded and provided with a nut and washer F; G is a cupshaped piece which has a tapered seat for the disk D and is secured tothe carburetor body; the annular space between the spring E and thewalls C is occupied by an electric coil H; this coil has two connectionsI andJ, or of course it may be grounded when only one connection isrequired. However, it is preferable not to ground at this point owing tothe proximity of the gasoline vapors. On the other end of the shaft B isa stamping K which is controlled by a lever L, to which it is connectedby the spring M. by the following means. The projecting pin a showninFigures I and III is mounted on the stamping K anda correspondingpin 1) is mounted on the lever L, the spring M being in tension betweenthe two pins on and b. a is slightly off center with reference to thepin 6 and the throttle shaft B so that the tendency of the spring M isto rotate the shaft B in a clockwise direction so as to draw theeccentric valve A into the open position.

The lever L is also provided with a stop stop 6 of the stampin 71: sothat the throt .tle valve 0, throttle s aft B, stamping K,

and lever L move together. the stops dand e being held in contact witheach other'by the tension of the spring M. Another stop f, correspondingto the stop 0, is provided on \the stamping K, which stop is adapted tocontact with the stop d when the lever L moves in a clockwise directionwith reference to the throttle valve A, throttle rod B, and stamping K.When in this latter position the spring M is obviously extended so as toexert its maximum torque on the throttle shaft B. This torque isbalanced by the action of the air flo'w upon the throttle valve A(eccentrically mounted on the throttle rod. B), this action tending torotate the valve A against the action of the spring M. W is the startingmotor; X is the starting switch; Y is the storage battery; Z and are theground connections. H is a bell crank lever operated simultanepusly withthe starting switch X as an alternative to the electro-magnet GH.

Referring to Figure II, A is the choke valve; N is the air entrance; 0is the choke tube; P is the main throttle; Q is the fuel nozzle; R isthe air vent; S is the needle; T is the main fuel outlet; U is the lowspeed tube; V is the low speed outlet.

Figure III is merely a side elevation of lever L, spring M, and stampingK.

Operation: he normal-operation of the choke valve A and the choke leverL is as follows:

When the engine has been running for some considerable time and istherefore warm the choke valve A 15 in its wide open position, as shownin Figures I and III. and

the entire mechanism is inoperative. hen running vwith a cold engine thechoke valve A is closed by moving the choke lever L 70 (see Figure III)in a clockwise direction. This causes the choke valve A to just closethe air entrance N and to exert a slight pressureon the walls of the airentrance In very cold weather the lever L is moved an additional in aclockwise direction, thereby causing the stop d of the lever L tocontact with the stop f of the stamping K and thereby positively lockthe choke valve A and thus effectively seal the air entrance N.

Obviously in thesetwo extreme namely the position shown in Figures I andIII and the position described above in which the stop d contacts withthe stop 7 there no need of any auxiliary device for controlling thechoke valve A; but in the intermediate positions, choke valve A isclosed but the spring M is not fully extended, it is desirable toprevent the opening of the choke valve A when the electrical startingmotor is slowly cranking the engine. In other words it is positions,

desirable to adjust the lever L into the lever L at this critical momentimmediately after the starting operation that this invention has beendevised. I

Then the starting motor is operated and the starting switch depressed,the electromagnet GH is energized by the electric current flowing from Ito J. a The piece D,

which is of soft iron, is thereby drawn by magnetic force on the seat ofthe mouth of theannular bowl G, The shaft B is thereby the engine thatis'to say when the P locked in position and the full suction of acts onthe fuel nozzle Q, and the vent R (Fig. II). On releasing the startingmotor the valve A is restored to its normal position, as determined bythe manually controllable lever L which is connected to the choke valverod B through the spring M and the piece K, which is riveted to the endof the shaft B. When the electro-magiiet G is not used the lever H maybe arranged to serve the same purpose, that is to lock the springcontrolled choke valve whilst the starting motor circuit is closed;lVhen the engine to which the device is attached is hot, choking isneither needed nor desirable, and then it is possible, by manuallyopening the valve A, to lock the valve A in the open position andthereby avoid drawing in an excessive quantity of always closed wheneverthe electric current was closed by X and the starting mot-or put inoperation.

When the bell crank lever H is used the same results are secured as whenthe electromagnet GH is used, but, of course, the controls are morecomplicated as the carburetor is located some distance away from thefoot control of the startingswitch.

With either construction the flexible air valve A is locked in positionwherever it may be, when the starting motor is in operation.

Figure II shows the choke valve in the closed position and the throttlevalve in the idling position. Obviously when it is desired to start theenginethe throttle valve must be opened at least 30 which case the'fuelissues directly into the Venturi tube 0 and not into the low speedbypass U. The position of the part shown, therefore, corresponds to lowspeed operation with a cold engine.

l/Vhat I claim is:

The combination of an internal combustion engine having electricstarting means controlled by a switch, a carburetor,'priming means forsaid carburetor comprising an automatic air valve responsive to theengine suction and located between said carburetor and the atmosphere,manual means for adjusting said air valve, common means for energizingthe electric starting means and locking said air valve, whereby thepriming ineans may be rendered either operative or inoperative to anydesired degree 'as determined by the manual adjustment of said airvalve.

In testimony whereof I afiix my signature. V

EARL HOLLEY.

